(Image Credit: Mel Evans/AP Photo)

President Obama today officially endorsed Newark Mayor Cory Booker for the U.S. Senate.

The president's endorsement comes after Booker easily clinched the Democratic nomination last week for the seat vacated by the late Democratic Sen. Frank Lautenberg.

"Cory Booker has dedicated his life to the work of building hope and opportunity in communities where too little of either existed," Obama said in a statement. "Whether as a college student working in East Palo Alto or as mayor of New Jersey's largest city, Cory has time and again taken on tough challenges, fought for the middle class and those working to join it, and forged coalitions that create progress - and that's the spirit he'll carry with him to Washington."

The endorsement comes as no surprise because several Obama-world hands have already been helping Booker with his Senate run, including 270 Strategies, a consulting group run by Obama's grassroots gurus Jeremy Bird and Mitch Stewart. And Booker's campaign manager Addisu Demissie also worked for the Obama campaign.

In his endorsement, Obama also cited Booker's advocacy for stricter gun laws and his efforts to attract new businesses to Newark.

"I am humbled by President Obama's endorsement," Booker, 44, said. "If elected this October, I will go to the Senate to advance our shared vision of a nation where opportunity is available to anyone willing to work for it, and to ensure we're investing in the priorities that helped build America's middle class."

Booker faces tea party favorite and former mayor of Bogota, N.J., Republican Steve Lonegan in the general election.